Dental implement.



M. A. STEVENS.

DENTAL IMPLEMENT.

APPLICATION FILED mm: I3. 1918.

1,290,399., Patented Jan. 7, 1919.

barren s'raznce rannr ora ion,

MUJRBELL a. srrnvnzns, or nU'rLAnrn, VERMONT.

DENTAL IMPLEMENT.

Specification of Letters Patent. i

Patented an. 7, 11.9119.

Application filed June 13 1am Serial No. 239,790.

1 all whom it may concern Be itknown that I, MURRELL A. STEVENS,

a citizen of the United States, residing at useful Improvements in Dental Implements;

and I do hereby declare the following to be a full, clear, and exact description of the invention, such aswill enable others skilled .in the art to which it appertains to make and use the same; i

The present invention relates to improvements in dental implements in general, and more particularly relates to a dental implement for use in assembling the separable Parts of the handpiece ot' a dental engine.

Heretofore great difliculty has been ex perienced in putting together the separable members of a dental handpicce after the same have been disengaged in ortlcr to add the/Washers. The handpicce subjected to a great amount of friction and becomes worn and washer have to be added from time to time. The difiiculty in putting the members of the handpiecc together arises from the fact that the spring which is carricd by one of the members and which is adapted to engage with a rack bar carried by the other of said members and whereby the members are held together, has a tcndcncy to strike arts of the member by which the rack bar is carried when the members are brought axially together, which prevents the further axial movement of the members to their final position; and before the members are permitted to be moved farther together the spring must be moved out of the way of the part encountered. This is now generally done by passinga rod through the slot in the handpiece and into engagen'ient with .the spring, but this is attended with a great deal of difficulty and rcqui'ts the removal of the hand from one of the members of the handpiece.

I aim by my present invention to provide an improved implement which Will grip one of the members of the handpiece and at the same time hold the spring in a retracted position where it will be out of the way of all roiecting parts and which will be operable )y one hand, leaving the other hand free to hold thc opposite men'ibcr of said handpicce.

It is an object of the present invention to provide a simple, readily operable, and cheap instrument for carrying out the above specified purposes.

In the accompanying drawings forming a part of this application, and in which similar reference symbols indicate corresponding parts in the several views:

F lgure 1 shows a vertical sectional view with parts in elevation of themembers of a dental handpiece shown in separated condi: tion about to be assembled, and showing certain parts in elevation and section of my improved implement. a y

F ig. 2 is an enlarged cross sectional view taken on the line 2-2 in Fig. 1; and

Fig. .1 proved implement.

\ Referring now in detail to the drawings whcremI haveshown but a single embodiment of which my invention is susceptible, l V

and designate the two opposite members of a handpiece of a dental engine, and 3 represents the spring carried by the member 1 and cmploycd to hold the two members 1 and together when assembled. As shown,

this spring- 3 has the crooked end 4 adapted to engage the teeth of a rack bar carried by the member 2, which rack bar is not shown in the drawings. 1

in assembling, the members 1 and Qare brought axially opposite one another and moved longitudinally together so that the projecting reduced portion 5 on the memher 2 may enter the hollowed out lower portion of the upper IllBIl'lbQl' 1.-. The entrance or the projecting port-ion 5 will be arrested by the crmked end 4 of the spring 3, which has a tendency to swlng toward the right when mirestrained, and. which forms an I abutment against which the portion 5 will strike. It is the practice at the present time to remove the spring from the path of the portion 5 by passing a rod through the elongatcd slot (5 in the upper member 1 and thrusting such rod against the spring 3170 force it to a retracted position Where it will project into and slightly beyond an elongated slot 7 made in the opposite side of the upper member 1, as shown in Fig. 1.

In accordance with the present invention 1 provide the improved implement which consists of two parts or jaws 8 and 9, one of the jaws being movable with respect-to the other. The jaws are adapted to support the upper member 1 and at the same time hold the spring 3 in tho retracted position shown in Fig. 1. One part 8 of the improved implement is formed with a recess 10 adapted to receive the spring 3; such is a perspective view of my im- .6 and engage the spring 3 in t the manner illustrated in Fig.

as indicated at 14;

jaw or part 8 and opens through both sides thereof so that when the implement is in operative position the recess 10 lies with its open ends in the same direction with the slot 7. These lips 11 and 12, as shown to advantage in Fig. 2, are made to tightly embrace the wall of the member 1 in such position that the recess'l0 will be in registry with the slot 7 and in a position to receive the spring 3 ,when the same is forced to the retracted position. The spring is forced back by a flat prong or angled end 13 projecting from and carried by the opposite part 9 of the implement, which is arranged to enter through the opposite elongated slot the manner clearly shown in Figs. 1 and 2.

Although the implement may take other forms, I find it convenient to make it up in 3 wherein the jaws 8 and 9 are crossed and pivoted such jaws being continued to the rear side of the pivot point where they are formed into the curved or other handles 15 and 16.

In use, after the handpiece has been disassembled and the washers added, the handpiece is re-united by first taking in hand the upper member 1 and engaging the parts of the improved implement therewith. This is done by first opening the jaws 8 and 9 by means of the handles 15 and lfi'and bringing such jaws to a proper position whereat they may be closed in a way to cause the flattened prong 13 to enter through the slot 6 and the opposite jaw 8 to engage against the outer part of the member 1 in substantiallv the osition shown in Figs. 1 and2.

. curved gri After being engaged in this mannen the spring 3sis moved to the retracted position out of the path of the portion 5, and a single hand may be employed to hold the two handles 15 and 16 closed and which, by so doing, both supports the member 1 and holds the spring 3 retracted. The other hand is then free to grasp the lower member 2 of the handpiece, and the members may then be axially fitted together until the portion 5 of the member 2 has passed the lower crooked end of the spring 3, whereupon the implement may be removed to withdraw the prong 13 and the members 1 and 2 may thereafter be forced home.

It is obvious that those skilled in the art may vary the details of construction and arrangements of parts without departing from the spirit of my invention, and therefore I do not wish to be limited to such features except as may be required by the claim.

I ,claim:

A dental implement for use in assembling the parts of a dental handpiece of the usual cylindrical form, and containing the usual leaf spring, the said handpiece being slotted on opposite sides abreast said spring, said implement comprising two bars crossing each other and pivoted together each of said bars being provided with a handle at one side-of said pivot, and one of said bars being provided at its opposite end with an and the opposite, bar being provided with ping faces adapted to fit the extenor of t- 1e handpiece, and with a transverse notch intermediate of said faces and adapted to receive said spring when pressed outward by the opposite gripping arm, substantially as described.

- In testimony whereof, I aflix my signature. ,85 V

MURRELL A. STEVENS. 

